1. wzpan在前文给出extra的配置是：

12

extra: - key: valu

而在后文给出的demo却是：

12

extra: bibliography: "/path/to/bibfile.bib"

bibliography前面怎么少了一个-？有蹊跷！

2. 解决办法是啥?

man pandoc读了一会儿帮助文件，忽然发现这么一段：

–bibliography=FILE

Set the bibliography field in the document’s metadata to FILE, overriding any value set in the metadata, and process citations using pan‐ doc-citeproc. (This is equivalent to –metadata bibliography=FILE –filter pandoc-citeproc.) If –natbib or –biblatex is also supplied, pan‐ doc-citeproc is not used, making this equivalent to –metadata bibliography=FILE. If you supply this argument multiple times, each FILE will be added to bibliography.